If you have been reading this blog for a while, you know that I have a weakness for time trial bikes. Like almost every new time trial machine, the new Cervelo P5 looks fast… even sitting still (and I am sure that it is a very fast bike with the right motor). What’s different about this bike though? Cervelo points out on their website four features that define the P5. I won’t rehash all the marketing copy here, but the hydraulic brakes by Magura are certainly one interesting detail that is generating a lot of attention. More interesting to me though is the fact that this frameset design exploits a few UCI loopholes quite nicely. Velonews has a great article about the P5 that explains how Cervelo engineers used the UCI rules to work to their advantage. Through the use of “gussets” that support the frame tubes, “the P5 actually has a 6:1 ratio, yet it still abides by the UCI’s 3:1 rule.” That 6:1 airfoil profile can be found on the version of the bike that is UCI legal, but there is another tri specific version (seen in the pictures here) with a fork design that completely ignores the UCI rules.

“Perhaps the results of an athlete like TJ Tollakson will get the big players in industry to think about developing more triathlon specific bikes that don’t comply with the UCI’s restrictions. After all, as long as there are triathletes choosing to ride old Softrides and Zipps over new Shivs, P4s, and Time Machines, there seems to be a market.”

This a great example of a bike designed and developed with that market in mind, and I suspect that we will see many more in the near future. As long as triathletes don’t have to comply by UCI rules, why shouldn’t bike companies give them the products that they want?

Frankly I’m surprised they still use such large brake levers. If the purpose of the bike is to be riding on a course solo at top speeds, the needs of a fancy brake system are so low that I would think a single brake with a tiny lever would suffice. Do they ever brake other than at the finish line?

I can’t remember if it was here or elsewhere, but I recall a woman racing on a bike that had the brake lever integrated into the bars. There was just a wide button that worked the brake, which didn’t add to the drag.

Good point. For a TT course with many sharp turns, good brakes may be necessary. The few triathlon courses I have seen are usually pretty straight and open though, requiring little or no braking until the end. Regardless, Magura claims that these brakes are the “fastest on the market” because the rider “can stay faster for a longer time”, but it seems like that would be a bigger factor in a mass start race than in one against the clock.

I don’t buy it. The only time brakes ever come into play is on out and back courses. You can lose significant time at the turnaround, but the limiting factor is never the brakes themselves. Dual pivots with good pads already have enough grip to either flip the bike or skid the front end.

I wouldn’t say pointless. One of the biggest headaches in maintaining an aero bike has always been hidden cables. It’s a nightmare to replace the cable housings, and there are so many kinks and bends that nothing works quite right. Wires and hydraulic lines don’t mind tight corners, and are good for the life of the frame.